库水位上升对茨哈峡4#倾倒体的稳定性研究  

Study on the influence of water level rise on 4# toppling slope of The Cihaxia Hydropower Station stability

作　　者：杨敏[1] 李宏儒[1] 李宁[1] 李国锋[1] 安晓凡 YANG Min;LI Hongru;LI Ning;LI Guofeng;AN Xiaofan(Institute of Geotechnical Engineering,Xi′an University of Technology,Xi′an 710048,China)

机构地区：[1]西安理工大学岩土工程研究所,陕西西安710048

出　　处：《西安建筑科技大学学报（自然科学版）》2019年第2期235-242,共8页Journal of Xi'an University of Architecture & Technology(Natural Science Edition)

基　　金：国家自然科学基金项目(11572246;51179153)

摘　　要：库水位上升产生的浮力作用,将改变原来的水-边坡作用环境,不利于库区边坡稳定.结合茨哈峡4#倾倒体现场踏勘调研情况,根据倾倒体的环境地质条件,探讨了该库岸倾倒体的成因机制和演化过程.利用数值模拟方法,采用FLAC3D有限差分软件建立三维模型,运用强度折减理论对该库岸倾倒边坡的稳定性进行了计算分析,将边坡关键点处的位移是否突变和塑性区是否贯通作为边坡的失稳判据.结果表明:倾倒体的稳定性受库水位上升的影响较为明显;倾倒体在天然状况下是稳定的,此时倾倒体的稳定系数为1.78;随着库水位的上升,倾倒体安全系数逐渐降低,当库水位上升至2 990 m(水位355 m)时,倾倒体的稳定系数为最小,其值为1.12,小于边坡设计安全系数.为了确保安全,建议对该倾倒体采取监控措施.The buoyancy caused by the rise of the reservoir water level will change the original environment of water-slope interaction, which is not conducive to the stability of the slope in the reservoir area. Based on the site investigation of the toppling mass in 4# toppling slope of Cihaxia Hydropower Station and the corresponding geological environment, the genetic mechanism and evolution process of the toppling mass at the bank of the reservoir were discussed. By using the numerical simulation method and the FLAC3D finite difference software, a three-dimensional model is established, and the stability of the toppling slope of the reservoir bank is calculated and analyzed by strength reduction theory. The displacement of the slope at the critical point and the consistency of the plastic zone is through are taken as the criterions for slope instability. The results show that:(1) and the consistency of the stability of toppling mass is obviously affected by the rise of the reservoir water level.(2) The toppling mass is naturally stable with the stability coefficient at 1.78.(3) With the increase in water level of the reservoir, the safety factor of toppling mass decreases gradually. When water level of reservoir rises to 2 990 m (Water level 355 m), the stability coefficient of the toppling mass is the smallest as 1.12, which is less than safety factor of slope as designed. To ensure safety, it is recommended to monitor such kind of toppling mass.

关 键 词：库水位上升 强度折减法 三维分析 安全系数 

分 类 号：P642.[天文地球—工程地质学] TU471.5[天文地球—地质矿产勘探]